1. Technical Field
The present invention relates to a vehicle bearing device.
2. Description of Related Art
FIGS. 6 and 7 show a conventional vehicle bearing device 100.
As shown in FIG. 7, the vehicle bearing device 100 has a hub 110. As shown in FIG. 6, the hub 110 has a cylindrical portion 111, and a flange portion 120. The flange portion 120 has five bolt hole formation portions 121, a pin hole formation portion 123, and four ribs 125. The bolt hole formation portions 121 have hub side bolt holes 122. The five bolt hole formation portions 121 are formed at equal intervals in the peripheral direction of the flange portion 120.
The pin hole formation portion 123 is formed between one of the bolt hole formation portions 121 adjacent to each other and another bolt hole formation portion 121. The pin hole formation portion 123 has a hub side pin hole 124. Each rib 125 is formed between one of the bolt hole formation portions 121 adjacent to each other and another bolt hole formation portion 121. The pin hole formation portion 123 and the four ribs 125 are formed at equal intervals in the peripheral direction of the flange portion 120. Each rib 125 differs from the pin hole formation portion 123 in that it has no hub side pin hole 124; otherwise, it is of the same construction as the pin hole formation portion 123. Patent Document 1 discloses a vehicle bearing device having a structure similar to that of the conventional vehicle bearing device 100.
FIG. 7 shows the relationship between the vehicle bearing device 100 and a brake rotor 130.
The brake rotor 130 is fixed to the hub 110 by five wheel bolts 140 and a pin 150. The brake rotor 130 has five rotor side bolt holes 131 and a rotor side pin hole 132.
The brake rotor 130 is fixed to the hub 110 by the following procedures.
First, the hub 110 of the vehicle bearing device 100 is superimposed on the brake rotor 130. The hub side pin hole 124 is opposite to the rotor side pin hole 132. The hub side bolt holes 122 are opposite to the rotor side bolt holes 131.
Next, a pin 150 is inserted into the rotor side pin hole 132 and the hub side pin hole 124. The pin 150 is inserted into the rotor side pin hole 132 from the brake rotor 130 side. Next, one wheel bolt 140 is inserted into a hub side bolt hole 122, a rotor side bolt hole 131 and a bolt hole (not shown) foamed on a wheel. This one wheel bolt 140 is screwed into the rotor side bolt hole 131 from the side opposite to the brake rotor 130 side. By the same procedure, the remaining four wheel bolts 140 are inserted into the hub side bolt holes 122, the rotor side bolt holes 131 and the bolt holes (not shown) formed on the wheel.
Patent Document 1: US Patent Application Publication No. 2011/0127826